<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>堆快照监控内存</title>
</head>
<body>
    <button id="btn">add</button>
</body>
<script>
    var tempEle;

    function fn() {
        var ul = document.createElement('ul');
        for (let i = 0; i < 10; i++) {
            var li = document.createElement('li');
            ul.appendChild(li);
        }
        tempEle = ul;
        
        tempEle = null;
    }

    document.getElementById('btn').addEventListener('click', fn);
</script>
</html>